Platinum black (Pt black) is a fine powder of platinum with good catalytic properties. The name of platinum black is due to its black color.
Platinum black is widely used as a thin film covering solid platinum metal, forming platinum electrodes for applications in electrochemistry. The process of covering platinum electrodes with such a layer of platinum black is called "platinization of platinum". The platinized platinum has a true surface area much higher than the geometrical surface area of the electrode and, therefore, exhibits catalytic action superior to that of shiny platinum.
Platinum black powder is used as a catalyst in proton exchange membrane fuel cells. In common practice, the platinum black is either sprayed or hot pressed onto the membrane or gas diffusion layer. A suspension of platinum black and carbon powder in ethanol-water solutions serves to optimize the uniformity of the coating, electrical conductivity, and in the case of application to the membrane, to prevent dehydration of the membrane during the application.
Read more about Platinum Black: Manufacturing of Platinum Black Powder, Process of Platinization of Platinum Metal, Platinum Metal Sponge, Potential of Platinized Platinum Versus Shiny Platinum, See Also
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